No abstract available

No abstract available

No abstract available

[en] Published in summary form only

No abstract available

[en] A series of programs of common modular structure have been written in APL for the interpretation of nuclear magnetic resonance and relaxation data in isotropic or anisotropic solutions (liquid crystals). After giving an outline of the computation methods, several examples are reported of the applications of these programs to conformational studies by means of the nuclear relaxation and of the diamagnetic of paramagnetic shifts of resonance lines. These programs are also convenient for studies of dipolar and quadrupolar splittings or chemical shift anisotropy in liquid crystals

[en] This volume contains one chapter which is in INIS scope, dealing with solid state NMR spectroscopy applied to zeolites. (H.W.). refs.; figs.; tabs

[en] A short introduction is given into the basic principles and experimental techniques of high-resolution solid state NMR, followed by a concise survey of the main information retrievable from the NMR spectra and its application to structural studies of zeolites and related systems. (author).; 55 refs.; 14 figs.; 2 tabs

[en] The proton spin T₁ relaxation dispersion in the smectic A and C phase of TBBA, and for comparison also in the nematic phase, have been studied using time dependent fast field-cycling techniques in the Larmor frequency range from νp = 100 Hz to 44 MHz. Our measurements considerably extend recent ones by Blinc et al., performed with other NMR methods for frequencies >= 140 kHz. The new experimental data are consistent with the reported ones for Sm C but not for Sm A, the difference being that the essential T₁ dispersion observed with our technique occurs at much lower frequencies, namely below about 100 kHz. As a consequence, the relaxation dispersion for both smectic phases looks very similar. It can be described quantitatively in terms of relaxation by 'nematic-like' order fluctuations, self-diffusion, and by a third molecular mechanism with (for simplicity) Debye-like power spectrum, which is possibly a second type of order fluctuation or a molecular rotation about the short axis. The analysis reveals surprisingly far going parallels between the spin relaxation of simple smectics and that of high-temperature nematics like PAA. (orig.)

[en] The improved system of basis functions permitting to decrease the error of solid NMR spectra decay up to noise, including polymer spectra is suggested and tested